This invention relates generally to construction vehicles commonly referred to as tractor-loader-backhoes and, more particularly, to an improved control mechanism for operating the backhoe.
Backhoe control mechanisms have generally been configured in one of three standard orientations. A four lever control mechanism controls the four hydraulic functions of the backhoe assembly, i.e. lift, swing, bucket, and crowd, individually with each control lever effecting operation of one of the corresponding hydraulic cylinders. A three lever control mechanism utilizes foot pedal controls for the swing of the backhoe assembly, while the three remaining hydraulic functions are controlled through appropriate control levers. A two lever control system controls all four hydraulic functions through the two control levers with two functions being controlled through fore-and-aft movements of each respective control lever, and the remaining two functions being controlled through transverse movements of the control levers.
The control mechanism is associated with a valve body having a plurality of spools controlling the flow of hydraulic fluid to the hydraulic cylinders corresponding to each respective function of the backhoe assembly. Typically, each type of control mechanism described above has the spools oriented in a different configuration for proper alignment with the respective control member. Accordingly, conversion of a backhoe control mechanism from one type of system to another has been cumbersome and involves a restacking of the valve body. Accordingly, conversion of one type of control system to another has involved a significant amount of time and expense. A further complication lies in the orientation of the control handles of each different control system as the handles are positioned in a different location with each respective type of control mechanism.
Accordingly, it would be desirable to provide a backhoe control mechanism that would facilitate the conversion of one type of system to another for the convenience and comfort of the operator so that he may utilize the type of control mechanism with which he is accustomed.